APPARATUS FOR VULCANIZATION AND MOULDING OF VEHICLES TYRES

Description

[0001] The present invention relates to an apparatus for moulding and vulcanisation of tyres for vehicle wheels.

[0002] In a tyre production cycle it is provided that, subsequently to a building process during which a green tyre is obtained through assembling of the different tyre components, a moulding and vulcanisation process be carried, said process aiming at stabilising the tyre structure according to a desired geometric conformation usually characterised by a particular tread pattern.

[0003] To this end, the tyre is introduced into a vulcanisation apparatus of the type disclosed, for example, in US Patent No. 5,234,326 in the name of the same Applicant,.

[0004] This apparatus comprises a pair of plates adapted to be moved close to each other and designed to operate on the tyre bead and sidewalls, and at least one crown of circumferentially distributed mould sectors radially movable close to each other to operate at the tyre tread band. In more detail, the plates and sectors are mutually movable between an open condition at which they are spaced apart to enable loading of the tyres under manufacture and a closed condition at which they define a moulding cavity having a geometric configuration matching the outer surfaces of the tyre to be obtained. For the moulding and vulcanisation operation, a vulcanisation bladder of elastomeric material filled with steam and/or other fluid at high temperature and pressure and placed inside the tyre enclosed in the moulding cavity, is provided to be inflated. In this way, the tyre is pushed against the inner walls of the moulding cavity and stabilised into the geometric conformation imposed on it, following cross-linking.

[0005] The moulding sectors, supported by appropriate sector carriers, are brought to the closed or open condition by a vulcanisation press that, acting by means of mechanical connections on the sector carriers, operates sliding of the latter on suitable guide elements and, as a result, movement of the mould sectors.

[0006] In the technical field of the invention were also known documents EP653293, EP1415781, US2006/0008547, US5204036, WO2005/115710 and EP569909, defining the general state of the art.

[0007] EP653293 discloses a mould having sectors. The mould is designed so that, during the moulding phase, the moulding elements are all equidistant by virtue of members providing elastic repulsion between them.

[0008] EP1415781 discloses a vulcanizing mould for a tire in which the capacity of venting air through between the moulding pieces of the sector mould is significantly enhanced. A tread ring for vulcanizing and shaping a tread of the tire comprises plural sector moulds which are separately formed in the circumferential direction so as to be brought into surface contact with each other. Each of the sector moulds comprises segments and plural movable moulding pieces circumferentially aligned and disposed on the inner surface side of the segment, and each of the movable moulding pieces of each sector mould is urged away from each other.

[0009] US5204036 discloses a method for molding articles, particularly tires, of different diameters/circumferences including a plurality of pitches defining a mold cavity, the pitches having transverse faces in generally face-to-face abutment in a closed position of the mold cavity, and at least several of the pitches being of different lengthwise sizes. The pitches in the closed position of the mold cavity defining a predetermined mold configuration which includes portions at angles to the length of the article molded in the mold cavity.

[0010] US2006/0008547 discloses a tire mould in which a mould for moulding a tire tread comprising segments partitioned in a tire circumferential direction. The segments comprise a plurality of pieces partitioned in the tire circumferential direction, with only one of the pieces of the each segment being fixed while all other pieces are movable in the tire circumferential direction.

[0011] EP569909 discloses a sectorised mould for tyres wherein the peripheral ring is constituted by a set of metal sheets bearing on each other and stacked so as to be mutually pushing each other back. The ring therefore has the permanent tendency to increase in diameter. This tendency is combated by, for example, a conical shrink-fit element (hoop) which radially and simultaneously pushes back all the metal sheets.

[0012] WO2005/115710 discloses a vulcanization-molding process wherein a green tire is vulcanized in a cavity which is defined by a core made of rigid material and having an outer shape corresponding to the inner shape of a product tire, and by a vulcanizing mould surrounding the core, at least a portion of the moulding surface of a side ring constituting a portion of the vulcanizing mould is displaced in a direction to increase the cavity volume.

[0013] The Applicant has ascertained that the moulding and vulcanisation apparatuses as above described have some problems.

[0014] In fact, it was observed that during shifting of the mould sectors, above all towards the closed condition, sliding of the sector carriers on the respective guide elements, due to the weight of the sector carriers themselves, may involve jamming and uneven wear of the guide elements. In fact, the sector carriers by the action of their weight, tend to separate from the guide elements generating a relative slight rubbing between said parts.

[0015] The uneven wear of the guide elements may give rise to wrong positioning of the sector carriers in the closed condition and, as a result, of the mould sectors. Thus geometric and/or structural faults such as burr and step formation, can occur on the tyre tread band.

[0016] The applicant has perceived that important improvements can be achieved if during movement from and towards the closed condition the sector carriers are guided in their sliding along the respective guide elements in such a manner that they can slide substantially parallel to the respective guide elements.

[0017] The Applicant has now found that the presence of moulding faults in the tread band of a tyre following the vulcanisation operation can be eliminated or in any case reduced by providing at least part of the sector carriers with at least one spring device designed to exert a thrust action adapted to ensure a substantially parallel sliding of each sector carrier on the respective guide element.

[0018] The invention relates to an apparatus for moulding and vulcanisation of tyres for vehicle wheels, including a vulcanisation press and a vulcanisation mould associated with said press, said apparatus comprising:

• a pair of plates adapted to be moved close to each other and designed to operate on the tyre bead and sidewalls;
• a plurality of circumferentially distributed mould sectors adapted to be radially movable close to each other to operate at the tread band of the tyre; the plates and sectors being mutually movable between an open condition at which they are spaced apart to enable loading of the tyres being worked, and a closed condition at which they define a moulding cavity having a geometric configuration matching the outer surfaces of the tyre to be obtained;
• a plurality of sector carriers, designed to support the mould sectors and movable together with said sectors; each sector carrier (6) comprises a contact surface;
• actuating means operatively connected to the sector carriers and the vulcanisation press to operate movement of the mould sectors from the closed condition to the open condition and vice versa;
• a plurality of guide elements on which said plurality of sector carriers slides for movement of the mould sectors from the closed condition to the open condition and vice versa; each guide element (8) comprises a contact surface; characterised in that

at least part of said sector carriers has at least one first spring device designed to exert a thrust action capable of achieving sliding of each sector carrier on the respective guide element in such a manner that the contact surface of the sector carrier (6) and the contact surface of the respective guide element (8) slide on and parallel to each other.

[0019] Particular embodiments of the invention are the subject of the dependent claims.

[0020] In particular, preferably each spring device is designed to exert a thrust action in the direction of the vertical central axis Z-Z' of the sector carrier so as to maintain the latter pressed against the respective guide elements.

[0021] Preferably, each sector carrier comprises two spring devices each of which is located close to a side end of the sector carrier so as to carry out balancing of the forces acting on the vertical central axis Z-Z' of the sector carrier.

[0022] Each spring device may be advantageously provided to be disposed so as to abut, at least on closure of the mould, against a spring device of the adjacent sector carrier.

[0023] According to a preferred embodiment, each spring device is housed in a suitable seat formed in the sector carrier so as to project therefrom for abutment, at least on closure of the mould, against the spring device of the adjacent sector carrier.

[0024] Preferably each spring device comprises: a piston element and at least one spring adapted to exert a thrust action on said piston element.

[0025] In accordance with a preferred embodiment, at least part of the sector carriers has at least one second spring device designed to exert a thrust action directed radially outwards on the adjacent sector carrier.

[0026] Preferably, each sector carrier comprises two second spring devices located at the side ends of each sector carrier.

[0027] Advantageously, each second spring device comprises a plurality of leaf springs at least partly contained in a receiving seat formed in the sector carrier and fastened thereto in a removable manner.

[0028] Further features and advantages will become more apparent from the detailed description of a preferred but not exclusive embodiment of an apparatus for moulding and vulcanisation of tyres for vehicle wheels in accordance with the present invention. This description will be set out hereinafter with reference to the accompanying drawings, given by way of nonlimiting example, in which:

• Fig. 1 is a diagrammatic section view of part of the apparatus of the invention with a mould portion in a closed condition to enable processing of the tyre to be vulcanised;
• Fig. 2 is a diagrammatic section view of part of the apparatus of the invention with a mould portion in an open condition to enable removal of the vulcanised tyre;

• Fig. 3 shows a cross-section view along axis I-I' in Fig. 2 of a mould portion according to the present invention;
• Fig. 4 is an enlarged view of an embodiment of the first spring device in accordance with the invention;
• Fig. 5 is a cross-section view along axis II-II' in Fig. 2 of a mould portion according to the invention.

[0029] With reference to the drawings, an apparatus for moulding and vulcanisation of tyres for vehicle wheels in accordance with the present invention has been generally denoted with 1.

[0030] Apparatus 1 comprises a vulcanisation mould 2 associated with a vulcanisation press 3 only diagrammatically shown as it can be made in any manner convenient for a person skilled in the art. Mould 2 can be made up of two side portions 4 of annular conformation known as "plates" that are coaxially opposite along the central axis Y-Y' of the mould, axially movable relative to each other and substantially corresponding to the sidewalls of the tyre to be manufactured.

[0031] Disposed between said plates 4 is a central annular portion comprising a plurality of mould sectors 7 (usually in a number varying between four and ten), circumferentially disposed around the mould axis Y-Y'; a plurality of sector carriers 6, each provided to support several mould sectors 7 and a cone-shaped ring 5 at a radially outermost position with respect to the sector carriers 6 to support said sector carriers 6 in an axially slidable manner.

[0032] Sectors 7 are radially movable in both ways at right angles to the central vertical axis Y-Y' of the mould between a closed position (shown in Fig. 1) at which they define with the opposite plates 4 close to each other, a moulding cavity conforming in shape to the outer surfaces of the tyre to be obtained, and an open position (shown in Fig. 2) at which they are spaced apart, the plates 4 being spaced apart too, and allow removal of the vulcanised tyre.

[0033] The mould sectors 7 are designed to operate, when the mould is in a closed position, on the tread band of the tyre to define a so-called tread pattern in said band, and to this end they are provided, on their inner surfaces designed to come into contact with the tread band, with a plurality of surface ridges so as to generate longitudinal and/or transverse grooves delimiting the ribs and/or blocks of the desired tread pattern.

[0034] Plates 4 on the contrary and as previously mentioned, operate on the tyre sidewalls and, if raised portions are wished to be made thereon to define graphic identification elements of the tyre (such as the tyre trademark or size) for example, they are usually provided with corresponding cavities adapted to generate said raised portions.

[0035] The sector carriers 6 are jointly moved between a closed position and an open position by movement of the cone-shaped ring 5, in turn operatively connected to the vulcanisation press 3. In particular, the sector carriers 6 have an inclined surface 16 adapted to cooperate with a corresponding inclined surface 17 of the cone-shaped ring 5. A guide plate 8 is placed between the corresponding inclined surfaces 16 and 17, said guide plate 8 being secured in a removable manner to the inclined surface 17 of the cone-shaped ring 5 to enable sliding of the sector carrier 6 thereon. In accordance with the present invention, at least part of the sector carrier 6 plurality has at least one first spring device 10 designed to exert a thrust action in the direction of the vertical central axis Z-Z' of each sector carrier 6 to keep the latter pressed against the guide plates 8 of the cone-shaped ring 5, thereby ensuring a substantially parallel sliding of the sector carrier on the guide 8. Thus jamming of the sector carrier on the guide 8 is avoided during the closing movement of the mould, as well as uneven wear of the guide plates 8.

[0036] In the present specification by vertical central axis Z-Z' of the sector carrier it is intended a vertical axis parallel to the vertical axis Y-Y' of the mould and passing through the centre of gravity of the sector carrier itself.

[0037] According to a preferred embodiment shown in the drawings, each sector carrier 6 has two spring devices 10 disposed to a symmetric position relative to axis Z-Z' at the side ends of each sector carrier 6 so that said spring devices carry out balancing of the forces acting on the vertical central axis Z-Z' of the respective sector carrier 6; see Fig..3.

[0038] Each first device 10 is such disposed that, on closing of the mould 2, it abuts against a spring device 10 of the adjacent sector carrier 6. In detail, each spring device 10 is housed in a suitable seat 14 formed in the sector carrier 6 in such a manner as to jut out with respect to said seat 14 for abutment, during movement of the mould from the open to the closed condition, against a spring device 10 of the adjacent sector carrier 6.

[0039] Each device 10 has a piston element 9 and at least one spring 13 designed to exert a thrust action on the piston element 12. In detail, the piston element 12 is provided with an abutment head 22 and a rod 21 at least partly slidable within the seat 14.

[0040] The spring 13 is a helical-type spring coaxially mounted around the rod 21 to exert a thrust action on the abutment head 22.

[0041] According to another embodiment, as shown in Fig. 4, the spring device 10 could have two helical springs 13, 13' disposed one after the other so as to differentiate the type of thrust that is wished to be applied to the piston element 12. In this case, an abutment ring 11 is interposed between the springs 13, 13'.

[0042] Alternatively, the spring device 10 could be represented by any device known to a person skilled in the art and capable of exerting a thrust action on the sector carrier 6 to maintain said sector carrier pressed against the guide plates 8 of the cone-shaped ring 5, thereby ensuring a substantially parallel sliding of the sector carrier 6 on the guide plate 8.

[0043] In another preferred embodiment of the present invention, to ensure a simultaneous radial closing and opening movement of the sector carriers 6, capable of being relied on to obtain a precise final positioning, at least part of said sector carriers 6 has at least one second spring device 12 designed to exert a thrust action directed radially outwards on the adjacent sector carrier 6.

[0044] In detail, as shown in Fig. 5, each sector carrier 6 comprises two spring devices 12 disposed in a corresponding location at the side ends of each sector carrier 6.

[0045] Each second spring device 32 is made up of a plurality of radially superposed leaf springs 33, depending on the spring features that are wished to be obtained.

[0046] Each plurality of leaf springs 33 is contained at least partly in a receiving seat 15, formed in the sector carrier to which it is fastened in a removable manner, and at least partly in the adjacent sector carrier on which it exerts a force directed in a radial direction.

[0047] Alternatively, the second spring devices 32 can be represented by any device commonly known to a person skilled in the art and capable of exerting a thrust action directed radially outwards on the adjacent sector carrier 6 with respect to the sector carrier 6 to which such a device is fastened.

Claims

1. An apparatus for moulding and vulcanisation of tyres for vehicle wheels, including a vulcanisation press (3) and a vulcanisation mould (2) associated with said press (3), said apparatus comprising:

- a pair of plates (4) adapted to be moved close to each other and designed to operate on the tyre bead and sidewalls;

- a plurality of circumferentially distributed mould sectors (7) adapted to be radially movable close to each other to operate at the tread band of the tyre; the plates (4) and sectors (7) being mutually movable between an open condition at which they are spaced apart to enable loading of the tyres being worked, and a closed condition at which they define a moulding cavity having a geometric configuration matching the outer surfaces of the tyre to be obtained;

- a plurality of sector carriers (6), designed to support the mould sectors and movable together with said sectors (7); each sector carrier (6) comprises a contact surface;

- actuating means (5) operatively connected to said sector carriers (6) and said vulcanisation press (3) to operate movement of said mould sectors (7) from the closed condition to the open condition and vice versa;

- a plurality of guide elements (8) on which said plurality of sector carriers (6) slides for movement of the mould sectors (7) from the closed condition to the open condition and vice versa; each guide element (8) comprises a contact surface;

characterized in that:

at least part of said sector carriers (6) has at least one first spring device (10) designed to exert a thrust action capable of achieving sliding of each sector carrier (6) on the respective guide element (8) in such a manner that the contact surface of the sector carrier (6) and the contact surface of the respective guide element (8) slide on and parallel to each other.

2. An apparatus for moulding and vulcanisation of tyres for vehicle wheels as claimed in claim 1, wherein each first spring device (10) is such disposed that it exerts said thrust action in the direction of the vertical central axis Z-Z' of its sector carrier (6) so as to maintain the latter pressed against the guide elements (8).

3. An apparatus for moulding and vulcanisation of tyres for vehicle wheels as claimed in claim 2, wherein each sector carrier (6) comprises two spring devices (10) each of which is located close to a side end of the sector carrier (6).

4. An apparatus for moulding and vulcanisation of tyres for vehicle wheels as claimed in claim 3, wherein each spring device (10) is such disposed that it abuts, on closure of the mould (2), against a spring device (10) of the adjacent sector carrier (6).

5. An apparatus for moulding and vulcanisation of tyres for vehicle wheels as claimed in claim 4, wherein each spring device (10) is housed in a suitable seat (14) formed in the sector carrier (6) in such a manner as to jut out with respect to said seat (14) for abutment, on closure of the mould (2), against the spring device (10) of the adjacent sector carrier (6).

6. An apparatus for moulding and vulcanisation of tyres for vehicle wheels as claimed in claim 5, wherein each spring device (10) comprises: a piston element (12) and at least one spring (13; 13') adapted to exert a thrust action on said piston element (12).

7. An apparatus for moulding and vulcanisation of tyres for vehicle wheels as claimed in claim 1, wherein at least part of said sector carriers (6) has at least one second spring device (32) designed to exert a thrust action directed radially outwards on the adjacent sector carrier (6).

8. An apparatus for moulding and vulcanisation of tyres for vehicle wheels as claimed in claim 7, wherein each sector carrier (6) comprises two second spring devices (32), each located at a side end of the respective sector carrier (6).

9. An apparatus for moulding and vulcanisation of tyres for vehicle wheels as claimed in claim 7, wherein each second spring device (32) comprises a plurality of leaf springs (33) at least partly contained in a receiving seat (15) and fastened thereto in a removable manner.

Ansprüche

1. Vorrichtung zum Formen und Vulkanisieren von Reifen für Fahrzeugräder, mit einer Vulkanisierungspresse (3) und einer Vulkanisierungsform (2), die der Presse (3) zugeordnet ist, die Vorrichtung mit:

- einem Paar Platten (4), die angepasst sind, sich nahe zueinander zu bewegen und die dafür ausgestaltet sind, auf den Reifenfuß und die Seitenwände einzuwirken,

- mehreren umfängliche verteilten Formsektoren (7), die angepasst sind, radial nahe zueinander beweglich zu sein, um bei dem Laufflächenband des Reifens einzuwirken, wobei die Platten (4) und Sektoren (7) wechselseitig zwischen einem offenen Zustand, in dem sie beabstandet sind, um ein Beladen der zu bearbeitenden Reifen zu ermöglichen, und einem geschlossenen Zustand beweglich sind, indem sie einen Formungshohlraum mit einer geometrischen Konfiguration definieren, welche den äußeren Oberflächen des zu behaltenden Reifens entspricht,

- mehreren Sektorträgern (6), die dafür ausgestaltet sind, die Formsektoren zu lagern und die zusammen mit den Sektoren (7) beweglich sind, wobei jeder Sektorträger (6) eine Kontaktoberfläche aufweist,

- Betätigungsmittel (5), die operativ mit den Sektorträgern (6) und der Vulkanisierungspresse (3) verbunden sind, um eine Bewegung der Formsektoren (7) vom geschlossenen Zustand zum offenen Zustand um umgekehrt zu erzielen,

- mehreren Führungselementen (8), auf denen die mehreren Sektorträger (6) für die Bewegung der Formsektoren (7) vom geschlossenen Zustand zum offenen Zustand und umgekehrt verschieben, wobei jedes Führungselement (8) eine Kontakfoberfläche aufweist,

dadurch gekennzeichnet, dass
wenigstens ein Teil der Sektorträger (6) wenigstens eine erste Federeinrichtung (10), die dafür ausgestaltet ist, eine Drückbetätigung auszuüben, welche in der Lage ist, jeden Sektorträger (6) auf dem jeweiligen Führungselement (8) so zu verschieben, dass die Kontaktoberfläche des Sektorträgers (6) und die Kontaktoberfläche des jeweiligen Führungselements (8) aufeinander und parallel zueinander verschoben werden.

2. Vorrichtung zum Formen und Vulkanisieren von Reifen für Fahrzeugräder nach Anspruch 1, bei dem jede erste Federeinrichtung (10) so vorgesehen ist, dass sie die Drückbetätigung in der Richtung der vertikalen zentralen Achse Z-Z' ihres Sektorträgers (6) ausübt, sodass sie letztere gegen die Führungselemente (8) hält.

3. Vorrichtung zum Formen und Vulkanisieren von Reifen für Fahrzeugräder nach Anspruch 2, bei dem jeder Sektorträger (6) zwei Federeinrichtungen (10) aufweist, welche jeweils nahe an einem Seitenende des Sektorträgers (6) angeordnet sind.

4. Vorrichtung zum Formen und Vulkanisieren von Reifen für Fahrzeugräder nach Anspruch 3, bei dem jede Federeinrichtung (10) so vorgesehen ist, dass sie beim Schließen der Form (2) gegen eine Federeinrichtung (10) des benachbarten Sektorträgers (6) anliegt.

5. Vorrichtung zum Formen und Vulkanisieren von Reifen für Fahrzeugräder nach Anspruch 4, bei dem jede Federeinrichtung (10) in einem passenden Sitz (14), der in dem Sektorträger (6) ausgebildet ist, so aufgenommen ist, dass sie beim Schließen der Form (2) bezüglich des Sitzes (14) zur Anlage gegen die Federeinrichtung (10) des benachbarten Sektorträgers (6) hervorspringt.

6. Vorrichtung zum Formen und Vulkanisieren von Reifen für Fahrzeugräder nach Anspruch 5, bei dem jede Federeinrichtung (10) aufweist: ein Kolbenelement (12) und wenigstens eine Feder (13, 13'), die angepasst sind, eine Drückbetätigung auf das Kolbenelement (12) auszuüben.

7. Vorrichtung zum Formen und Vulkanisieren von Reifen für Fahrzeugräder nach Anspruch 1, bei dem wenigstens ein Teil der Sektorträger (6) wenigstens eine zweite Federeinrichtung (32) aufweist, die dafür ausgestaltet ist, eine Drückbetätigung auszuüben, die radial nach außen auf den benachbarten Sektorträger (6)gerichtet ist.

8. Vorrichtung zum Formen und Vulkanisieren von Reifen für Fahrzeugräder nach Anspruch 7, bei dem jeder Sektorträger (2) zwei zweite Federeinrichtungen (32) aufweist, welche jeweils an einem seitlichen Ende der jeweiligen Sektorträger (6) angeordnet sind.

9. Vorrichtung zum Formen und Vulkanisieren von Reifen für Fahrzeugräder nach Anspruch 7, bei dem jede zweite Federeinrichtung (32) mehrere Blattfedern (33) aufweist, die wenigstens teilweise in einem Aufnahmesitz (15) enthalten und daran lösbar befestigt sind.

Revendications

1. Appareil pour le moulage et la vulcanisation de pneus de roues de véhicule, incluant une presse de vulcanisation (3) et un moule de vulcanisation (2) associé à ladite presse (3), ledit appareil comprenant :

- une paire de plaques (4) agencées pour être déplacées l'une vers l'autre et conçues pour opérer sur le talon et les flancs du pneu ;

- plusieurs secteurs de moulage distribués circonférentiellement (7) agencés pour être radialement déplaçables l'un de l'autre de façon à opérer sur la bande de roulement du pneu ; les plaques (4) et secteurs (7) pouvant être mutuellement déplacés entre un état ouvert dans lequel ils sont séparés pour permettre une charge des pneus en train d'être travaillés, et un état fermé dans lequel ils définissent une cavité de moulage ayant une configuration géométrique correspondant aux surfaces extérieures du pneu en train d'être obtenu ;

- plusieurs supports de secteur (6), conçus pour supporter les secteurs de moulage et pouvant être déplacés en même temps que lesdits secteurs (7) ; chaque support de secteur (6) comprend une surface de contact ;

- des moyens d'actionnement (5) reliés fonctionnellement auxdits supports de secteur (6) et à ladite presse de vulcanisation (3) pour mettre en mouvement lesdits secteurs de moulage (7) depuis l'état fermé vers l'état ouvert et vice versa ;

- plusieurs éléments de guidage (8) sur lesquels lesdits plusieurs supports de secteur (6) coulissent pour faire coulisser les secteurs de moulage (7) depuis l'état fermé vers l'état ouvert et vice versa ; chaque élément de guidage (8) comprend une surface de contact ; caractérisé en ce que :

au moins une partie desdits supports de secteur (6) a au moins un premier dispositif à ressort (10) conçu pour exercer une action de poussée capable d'exercer un coulissement de chaque support de secteur (6) sur l'élément de guidage (8) respectif de manière que la surface de contact du support de secteur (6) et la surface de contact de l'élément de guidage respectif (8) coulissent l'une sur l'autre et parallèlement l'une à l'autre.

2. Appareil pour le moulage et la vulcanisation de pneus de roues de véhicule selon la revendication 1, dans lequel chaque premier dispositif à ressort (10) est agencé de sorte qu'il exerce ladite action de poussée dans la direction de l'axe central vertical Z-Z' de son support de secteur (6) de manière à maintenir ce dernier pressé contre les éléments de guidage (8).

3. Appareil pour le moulage et la vulcanisation de pneus de roues de véhicule selon la revendication 2, dans lequel chaque support de secteur (6) comprend deux dispositifs à ressort (10) disposés chacun à proximité d'une extrémité latérale du support de secteur (6).

4. Appareil pour le moulage et la vulcanisation de pneus de roues de véhicule selon la revendication 3, dans lequel chaque dispositif à ressort (10) est disposé de sorte qu'il vient en butée, lors de la fermeture du moule (2), contre un dispositif à ressort (10) du support de secteur adjacent (6).

5. Appareil pour le moulage et la vulcanisation de pneus de roues de véhicule selon la revendication 4, dans lequel chaque dispositif à ressort (10) est logé dans un siège approprié (14) formé dans le support de secteur (6) de manière à saillir par rapport audit siège (14) pour venir en butée, lors de la fermeture du moule (2), contre le dispositif à ressort (10) du support de secteur adjacent (6).

6. Appareil pour le moulage et la vulcanisation de pneus de roues de véhicule selon la revendication 5, dans lequel chaque dispositif à ressort (10) comprend : un élément formant piston (12) et au moins un ressort (13 ; 13') agencés pour exercer une action de poussée sur ledit élément formant piston (12).

7. Appareil pour le moulage et la vulcanisation de pneus de roues de véhicule selon la revendication 1, dans lequel au moins une partie desdits supports de secteur (6) a au moins un deuxième dispositif à ressort (32) conçu pour exercer une action de poussée dirigée radialement vers l'extérieur sur le support de secteur adjacent (6).

8. Appareil pour le moulage et la vulcanisation de pneus de roues de véhicule selon la revendication 7, dans lequel chaque support de secteur (6) comprend deux deuxièmes dispositifs à ressort (32), chacun situé sur une extrémité latérale du support de secteur respectif (6).

9. Appareil pour le moulage et la vulcanisation de pneus de roues de véhicule selon la revendication 7, dans lequel chaque deuxième dispositif à ressort (32) comprend plusieurs ressorts à lame (33) au moins partiellement contenus dans un siège réceptionneur (13) et fixés à ce dernier de manière amovible.

Drawing